﻿////////////////////////////////////////////////////////////////////////////////////////////////////
//
// VSCoverageToEmma - Visual Studio Coverage file to Emma converter
// Copyright (c) Kouji Matsui, All rights reserved.
//
// * Redistribution and use in source and binary forms, with or without modification,
//   are permitted provided that the following conditions are met:
// * Redistributions of source code must retain the above copyright notice,
//   this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
//   this list of conditions and the following disclaimer in the documentation
//   and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
// EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
////////////////////////////////////////////////////////////////////////////////////////////////////

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Text;
using System.Threading;

namespace System.Threading.Tasks
{
	public static class Parallel
	{
		public static void ForEach<T>(IEnumerable<T> enumerable, Action<T> action)
		{
			Debug.Assert(enumerable != null);
			Debug.Assert(action != null);

			var exceptionList = new List<Exception>();
			using (var wait = new ManualResetEvent(false))
			{
				var count = 1;
				foreach (var item in enumerable)
				{
					Interlocked.Increment(ref count);

					ThreadPool.QueueUserWorkItem(new WaitCallback(p =>
					{
						try
						{
							try
							{
								action(item);
							}
							catch (Exception ex)
							{
								lock (exceptionList)
								{
									exceptionList.Add(ex);
								}
							}
						}
						finally
						{
							if (Interlocked.Decrement(ref count) == 0)
							{
								wait.Set();
							}
						}
					}));
				}

				if (Interlocked.Decrement(ref count) == 0)
				{
					wait.Set();
				}

				wait.WaitOne();
			}

			if (exceptionList.Count >= 1)
			{
				throw new AggregateException(exceptionList);
			}
		}

		public static void Invoke(params Action[] actions)
		{
			ForEach(actions, action => action());
		}
	}
}
